Effects of low temperature on postharvest ripening and starchiness in ‘Cuixiang’ kiwifruit

Abstract

Low temperatures can accelerate the postharvest ripening of kiwifruit ( Actinidia deliciosa ). However, low temperature-treated ‘Cuixiang’ kiwifruit develop a starchy taste which is unacceptable to consumers. Therefore, the present study aimed to produce ready-to-eat ‘Cuixiang’ kiwifruit using proper temperature management. Compared to room temperature (20 ± 0.5 °C) treatment, low temperature (10 ± 0.5 °C) treatment accelerated the decrease in firmness and starch content, and the increase in soluble solid content (SSC), in ‘Cuixiang’ kiwifruit during postharvest ripening. However, the starch content was higher, while the SSC was lower, in low temperature-treated kiwifruit than in room temperature-treated kiwifruit at the same firmness stage. Rapid softening was observed in ‘Cuixiang’ under low temperature treatment, although the starch was not fully converted into sugar, resulting in starchy-tasting ready-to-eat ‘Cuixiang’. In an additional experiment, we transferred low temperature-treated kiwifruit to room temperature at different firmness stages and observed that ready-to-eat kiwifruit exhibited different SSCs according to when they were transferred. Overall, transferring low temperature-treated kiwifruit at a firmness of approximately 110 N to room temperature for three days resulted in ready-to-eat kiwifruit with >17 % SSC and no starchy taste. In conclusion, proper temperature management can reliably produce ready-to-eat ‘Cuixiang’ kiwifruit which will be acceptable to consumers. • Low temperature accelerated the starch degradation in ‘Cuixiang’ kiwifruit. • Low temperature treated kiwifruit were more starchy than untreated kiwifruit. • Starch was incompletely converted into sugar in low temperature treated kiwifruit. • Transferring chilled kiwifruit to room temperature produced ready-to-eat kiwifruit.

Topics & Concepts